The United States and Japan will step up their defence cooperation to deal with the threat from nuclear-armed North Korea as tensions in East Asia remain high, officials from the two allies said on Thursday.

Store water underground: scientists

Surplus rainwater should be stored underground instead of in dams to prepare for drought, a scientific study says.

The National Centre for Groundwater Research and Training has made the recommendation as the federal government tables Australia's first national Murray-Darling Basin plan in parliament.

Researcher Andrew Ross says Australia should be "banking" its water underground as an alternative to traditional dams during times of heavy rain.

"There is enormous national potential to store surplus water in aquifers, ensuring sufficient water is available for cities, homes, industry, farming and the environment when drought strikes," he said in a statement.

"Historically, Australians have relied on dams to provide water for agriculture and cities.

"This strategy is not sufficient to cope with increasing climate variability or droughts as demand for food and water grows."

Up to 3000 billion litres (GL) of water a year evaporates from the Murray-Darling Basin, he said.

Related Articles

That level of evaporation almost matches the 3200 billion litres a year the government is hoping to flush back into the Murray-Darling Basin, under its plan unveiled last week and tabled in parliament on Monday.

Mr Ross, who has researched integrated surface water and groundwater management, said storing water underground would ensure sufficient was available for Murray-Darling Basin agricultural production and environmental flows, and avoid the shutdown of irrigation.